When G. Wayne Clough began his tenure as head of the Smithsonian Institution in July 2008, he asked himself the question, "What will the Smithsonian be in 500 years?"

The answer? It's still not entirely clear. But as Clough prepares to retire from his position in October 2014 — announced Wednesday by the venerable museum and research institution — he leaves an organization undergoing a 21st century makeover.

Clough, former president of the Georgia Institute of Technology, arrived at a time when the 167-year-old Smithsonian was threatened by scandals and a crumbling infrastructure.

His predecessor as secretary, banker Lawrence M. Small, had resigned the previous year after it was revealed that he was using Smithsonian money to fund private travel and buy expensive gifts. In addition, the Smithsonian's facilities — including 19 museums and galleries, a zoo and nine research complexes, many lining the National Mall — needed an estimated $2.5 billion in repairs.

Congress, which funds about 70% of the Smithsonian's $1-billion annual budget, was highly critical of secrecy and mismanagement in the organization.

During his tenure as secretary, Clough has focused on initiatives in digital access, education and conservation. He also spearheaded the Smithsonian's first national fundraising campaign, which has raised $893 million in private contributions since 2008.

A particular emphasis was to expand the accessibility of the Smithsonian's collection by digitizing some of its 137 million artifacts, scientific specimens and works of art for online viewing and educational materials. But "it's not just a matter of digitizing your collections," Clough said. "It's what you do with those materials and how you allow people to interact with them."

He said he is proud of efforts to increase the vitality of the Smithsonian by hosting naturalization ceremonies at the Flag Hall in the Museum of American History, which holds the Star Spangled Banner. "It's a way to bring the museum to the people, rather than being a passive experience," he said.

"The challenge of 21st century museums is reaching beyond the boundaries of their four walls," said W. Richard West Jr., president of the Autry National Centry in Los Angeles and former director of the Smithsonian National Museum of the American Indian. "I applaud his efforts to do precisely that."

The Smithsonian's Board of Regents said it would form a committee to conduct a search for a new secretary.